In electro deposition for master phonograph records, it is customary to use metal in the form of cubes, granules or the like, as material for the anode. This material is placed in an electrically conductive receptacle with perforated walls for allowing the passage of the galvanic bath liquid and enabling the necessary ion migration. The receptacle is often in direct contact with a conductor placed in the bath and connected to the positive pole of a voltage supply. The conductor is usually titanium or other high-quality metal. For a galvanic deposition in very thin homogenous coatings it is important that particles do not become liberated from the anode material to form lumps in the coating on the object being coated. The anode material also contains chemicals which can disturb deposition on the matrix. In order to avoid such phenomenon, it is customary in the present state of the art to arrange a bag of some suitable textile, in which the anode material resides. The textile fabric must of course allow the easy passage of the bath liquid, while at the same time having a relatively dense structure to prevent small particles liberated from the anode material from streaming out into the bath liquid. To keep the bag intact while still providing good contact between said positive conductor and the anode material, contact means as described in the Swedish Pat. No. 7305397-7 can be used.
In spite of all precautions, it is occasionally unavoidable in practice that almost microscopic particles come into circulation in the bath liquid and become deposited on the matrix, resulting in a coating which is uneven in spots. Attempts have been made to solve the problem by arranging a further filter round the anode material receptacle, but it has been found that such arrangements unfavorably affect the galvanic deposition process. It is particularly desirable that a flow path which is as free and direct as possible shall exist between the anode material and the matrix, simultaneously as the bath liquid is brought into as intimate and turbulent flowing contact as possible with the anode material as well as the matrix.